CVE-2026-116734

Description

flatcc through 0.6.4 contains an integer overflow vulnerability in the check_header function of the FlatBuffers verifier because its overflow guard is dead code. On 32-bit builds, attackers can supply a crafted buffer offset that wraps the bounds check, causing an out-of-bounds read before the buffer and crashing the process.

References

• https://github.com/dvidelabs/flatcc
• https://github.com/dvidelabs/flatcc/blob/v0.6.4/src/runtime/verifier.c#L126-L137
• https://github.com/dvidelabs/flatcc/commit/0df9c097a19badc8bd22d93af8fd47bd291e5d9f
• https://hackmd.io/@haindpwn/flatcc-json-number-oob-read
• https://www.vulncheck.com/advisories/flatcc-through-0.6.4-out-of-bounds-read-via-verifier-check-header